442 100. FiLiCBS. 



t Clusters dorsal. Sing vertical, usually incomplete. Caps. 



Tribe I. POLYPODIES. Clusters nearly circular, without 

 an indusium, seated upon the back of the lateral veins. 



1. Cbtptoghammb. Clusters circular, at length confluent, 

 concealed by the reflexed margin of the ftond. — Barren and 

 fertile fronds dissimilar. 



2. PoLTrpOBiTTM. Clusters circular, naked ; edge of the frond 

 flat, not reflexed. 



.3. WooDSiA. Clusters circular, with an inferior involucre 

 divided at the edges into many capillary segments. 



Tr. II. ASPIDIEJE. Clusters nearly circular, covered by an 

 indusium, seated upon the back of the lateral veins. 



4 Lastbea. Indusium reniform, attached by the notch. 

 Veins distinct after leaving the midrib, not uniting with 

 those of the adjoining lobe. 



5. PoiTSTiCHUM. Indusium circular, attached by the centre. 

 Veins distinct after leaving the midrib. 



6. Ctstoptems. Indusium attached by its broad hooded 

 case under the clusters, with a long fringed free extremity 

 at first covering the capsules. 



Tr. in. ASPLENIEjE. Clusters oblong or linear, usually 

 covered by an indusium opening longitudinally on one side, 

 placed on the side of the lateral veins. 



7. Athtmum. Clusters oblong-reniform. Indusium open- 

 ing towards the central vein or midrib, margin fringed. 



8. AspLBNiTTM. Clusters long, straight. Indusium opening 

 towards the central vein or midrib, nearly flat. 



9. ScoLOPBNDMTJM. Clusters long, straight, 2 together. 

 Indusia of each pair opening towards each other. 



10. Oetebach. Lateral veins anastomosing; clusters attached 

 to their middle on the side next the midrib, except in the 

 lowest. Indusium (?) a narrow nearly erect membrane on 

 the back of the vein. Whole back of the frond covered 

 with chaffy scales. 



